Actually, I totally understand that, and even though it was my idea, I think you're right. It should be about you guys. Not me.

I'll opt out of it. Just let me know privately if there's anything I can do to help.
I'm not afraid of a few people who aren't disabled being in there. But I know from experience that if the number of healthy people comes even close to the number of disabled people, the healthy people will unintentionally and unconsciously take their rightful places above us in the social hierarchy, and when that happens, we'll be afraid to post in our own group. In a lot of cases, it doesn't matter whether people are trying to help us or not. It's still intimidating being around people who are less awkward than us. One of the loneliest feelings I've felt (and I feel it often) is being surrounded by healthy people who care about me, and like me, but still being completely unable to connect to them. When people who are not socially impaired act the way they normally do, it's impenetrable to us much of the time. And when they talk to us with the knowledge that we're disabled, they're often incredibly condescending by accident. They're every bit as clueless about communicating with us as we are about communicating with them, and I don't blame them for that. But it's still a problem. And either one of those things is what I would be afraid of causing by having a large number of people who don't have social issues in the group. That's all. You alone will not cause problems with the power balance of the group. The only thing that could do that is having enough healthy people to make acting normal, instead of acting slightly awkward, the thing that sticks out.
(to others reading this, yes, I'm aware that there's more to people's personas than simply "awkward" or "not awkward," and that there are varying levels of social impairment. I just didn't want to make this even more long winded than it already is by getting into that, haha.)
What I was getting to is that I would like you to be in the group. Because it was your idea, because you are supportive, and because of your brother.
For everyone else, I guess it's just up to you to decide if you think this group is going to be right for you. We are not going to ban you from the group because you seem normal. Lol. This is definitely not meant to be some sort of exclusive club. The things that seem like they would fit the best in this group are social anxiety disorder and autism.
I haven't heard from too many people on whether or not they'd be interested, but unless someone has another idea for the group and speaks up pretty soon, I'll get started on it!
EDIT: reading my post back, I probably don't seem disabled at all. Lol. I'm so much better at writing than I am at talking, it's not even funny. In writing, I can overthink stuff and rewrite it over and over until it makes sense without creating an awkward 30 second pause in the conversation while I contemplate whether my wording is going to make me sound like an idiot or not. XD ahaaaa